#include "c_string_case_conversion.h"
#include <string.h>

void to_lower(char* str, size_t len)
{
    for (int i = 0; i < strlen(str); i++) {
        if (str[i] >= 'A' && str[i] <= 'Z') {
            str[i] = str[i] + 32;
        }
    }
}

void to_upper(char* str)
{
    for (int i = 0; i < strlen(str); i++) {
        if (str[i] >= 'a' && str[i] <= 'z') {
            str[i] = str[i] - 32;
        }
    }
}
